Researchers in history education have argued the importance of closing the gap between how history is practiced in the discipline and how history is taught in schools. This study explores how three teachers who had learned to teach historical thinking in their teacher education program then implemented these practices in their first year of teaching. Data collected over a two-year period included observations of teachers in their methods courses and field placements; a pre-test and post-test administered before and after the completion of the teacher education program; observations of two units of instruction per teacher during their first year teaching; interviews with teachers during their teacher education program and first year of teaching; and analysis of documents collected over the two year period. Case studies revealed that one of the three teachers routinely taught historical thinking while the other two teachers implemented discipline-based practices less frequently. Cross-case analysis showed that each teacher's development and enactment of research-based practices varied. While the teachers' learning and working contexts, including teacher education and the school and district contexts, influenced if and how teachers taught historical thinking, a number of other factors contributed to teachers' decision making. These included teachers' understandings of the discipline, knowledge of how to make these thinking strategies accessible to students, vision and beliefs about teaching history, available tools and resources, and individual dispositions. This study highlights the intricate nature of how teachers learn and develop and offers insight into how researchers and practitioners can support new teacher learning. This includes continuing to improve teacher education to enhance lifelong learning; better aligning the goals of local schools and districts with those of research-based teacher education programs; and providing ongoing supports, such as induction programs sponsored by the University, once teacher candidates graduate. This study also suggests the need for communities of practitioners who share reform-minded goals and collaborate regularly to inquire about and improve practice. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]